they're in high rises in cities, in greenfield sites out in suburban areas, there tucked away in the back of offices. they are the way that most commerce takes place now. everyone has to have one. there are concentrations of the in the country. northern virginia, silicon valley. they're everywhere at this point. >> who runs them? >> a variety of players. companies that need these for their regular business owns some of these data centers, everything from walmart to microsoft. there is also a culture or commerce of renting space in dissenters. those are lesser-known names. one of them will sell you time on servers or space on servers. >> mr. glanz, what is contained inside these warehouse buildings? >> they're fairly boring places to visit. they are stacked with these modular computers called servers. one after the other after the other. it does not look like much. they draw a lot of electricity. all the things we rely on, we use the internet -- it all happens in these anonymous looking boxes called servers, thousands upon thousands of these things. >> if somebody has a gmail or yahoo